Then I would suggest you are being deliberately obtuse as the point is patently clear even to the dullest of intellects.
Being over the limit by the total of one schooner the morning after isn't a hanging offence, and most of us would have done this inadvertently at some time or another.
I remember having a few drinks with a mate one night, nothing major, just wine and beers after dinner. As I was clearly over the limit I decided to crash at his house. In the morning I drove home and got stopped for a breath test. I didn't have a hangover, I didn't feel rough, I felt pretty much normal. A bit tired was all. If you'd asked me what my alcohol reading was, I'd have put hand on heart and sworn I registered 0.00
I registered 0.04 - as a full licence holder I escaped caution but I was astounded I registered anything. There was no intent to drink drive, I had done everything in my power not to and had acted with good intentions. Yet a couple more schooners the night before and I would have been gone.
Alcohol takes longer to leave the system that people think and being over the limit, especially a zero limit for P platers, can be achieved very, very easily and without intent.